Circular knitting machine with air cleaner



Sept. 12, 1950 R. H. LAWSON CIRCULAR KNITTING MACHINE WITH AIR CLEANER 5 Sheets-Sheet 1 Filed Oct. 4, 1948 INVENTOR.

Sept, 12, 1950 R. H. LAWSON CIRCULAR KNI ETTING MACHINE WITH AIR CLEANER 3 Sheets-Sheet 2 Filed Oct. 4, 1948 INVENTOR. ROBERT H. LAWSON 3 Sheets-Sheet 5 R. H. LAWSON CIRCULAR KNITTING MACHINE WITH AIR CLEANER INVENTOR. ROBERT H.LAWSON 6 kills @220): eys

Sept. 12, 1950 Filed 001;. 4, 1 948 N NN Patented Sept. 12, 1950 UNITED STATES PATENT orries Robert H. Lawsomdlaconia, N. H., assignorto Scott at Williams, IncorpcrateiLaconia, N .H., acorporationof Massachusetts Appl'ication-October 4, 19iaseria1ivo. 52,.263

This invention relates to a circular knitting machine with air cleaner and more particularly to cleaning mechanism for such machines having stationary needle cylinders. One of the great problems in circular knitting machinery, and particularly underwear machines, is the removal of lint. Brushes of various types have heretofore been known to clean the needles, and compressed air has also been employed. Owing to the delicate nature of the yarn and the knitting operation, and the complexity of moving :air jets,

devices heretofore know-n have not been entirely satisfactory in underwear machines having stationary needle cylinders. My invention contemplatesa combination of brushes and compressed air which is so coordinated that the machine clears away the lint automatically at all points where it can cause trouble, without in any way disturbing the knitting functions.

In the drawings: Figure 1 is a perspectiveview of pertinent parts of a rib underwear machine having a stationary needle cylinder and dial, on which my novel air cleaner has been attached;

Figure '2 is a view in vertical section through the air valve control box with the cover removed; H Figure 3 is a perspective view of apattern chain form of control for the air jets when the machine is knitting successive garments, as distinguished from continuous fabric;

Figure 4 is a developed wiring diagram of the attachment shown in "Figs. 1,2 and ;3; while Figure 5 is a perspective view ,on .an enlarged scale .of the brushes and needles, showing the direction .of the air blast.

a circular underwear knitting machine with stationary needle cylinder containing lndepende ent needlesneither brushes .nor air jets alone provide satisfactory means of cleaning lint ofi the machine. I have found that brushes revolving about the needle cylinder can be combined successfully with an intermittently operated stationary air jet to keep the lint ofi the knitting elements. Ialso provide a specialjet for the yarn detectors as well.

In the example shown in the drawings there is a rib fabric underwear knitting machine having a stationary needle cylinder I, dial 2 and independent cylinder and dial latch needles 4,-3. Around the needle cylinder revolves a cam cylinder 5 and above the dial needles 3 thereis a cap 6 containing the dial needle cams and carrying on the dial cap is a .fixed brush 8 whose bristles face downward. I prefer to mount this "brush close to the periphery "of the cap and in contact with the upper face of the dial. "In this position the brush tends to roll the lint up into balls as the brush moves around the dial.

The brush arrangement which Ihave described willcollect the lint from the needles, dial and cylinder all around the machine, but some means must be provided to dispose of the small balls of lint rolled up by the fixed brush and the loose lint gathered by the revolving brush hereinafter described. For this purpose I employ an inter mitten-t fixed air jet located outside the machine at a single fixed point on "the circumference. There is a small let 13 directed against the brushes at a tangent tothe needle cylinder, as shown Fig. 1. By directing this stationary jet tangentially of the machine, the balls of lint and "the loose l-irit are easil blown off the machine when the air is turn-ed on and "the brushes pass the air jet. I find tliatit is necessary "to work this air jet only periodically, and the inter--' mittent action is obtained advantageously =by mechanism which will be hereinafter described.

on the revolving cam cylinder 5 is mounted a revolving brush 9. This is mounted at such an angle and elevation that it revolves about "its own axis as it is carried around the needle cylin= der. "It serves to collect lint atthe verge or edge of the cylinder '1' and dial 2, being in engagement withthe needles. The yarns come to the yarn guides 1 through lower yarn detectors in, upper yarn detectors H and yarn bobbins 12. There are ten feeds in the machine shown in the draw ings. Both 'the upper and lower yarn detectors are at'higher elevations than -the'yarn guides and the needle cylinder.

The jet 43 which constitutes the air jet for "th brushes and needles is located fairly close to the brushes and is so strong that it might upset the yarn or the detectors if it were located adjacent the detectors. However, the lint on the detectors has :merely settled there by gravity. I therefore provide a jet M in the generalneighborhood of the air jet l3 and needle cylinder, which jet M has :a small oriflcesand is aimed upwardly at either the upper or-thelower yarn detectors and generall in a direction counter to the direction of movement of the yarn toward the needles. The small orifice gives ,a small volume or airwel-l directed. The air twill dissipate itself suiiicientl-y before reaching the detectors sorthat it will not trip them or disarrange the yarns. On zthe other hand, the lint isl'so much lighter than the detectors that the small amount ref compressed :air

easily lifts the lint ofr the detectorsw-n-A air I have provided two types of air cleaner, the .1 1c

cooperative action with the bru hes cleaning. all

the needles, and the direct action cleaning the.

detectors.

The controls for making the air jets intermitreceive their air from an air valve lfi located in..-

a main control box I6. This air' valve is operated by a solenoid H which open the valve when I for any reason while the air is turned on, this ensures that the air will be turnedofi.

When the machine is making shaped garments and it is desired to cut the cloth at a definite point, I find it desirable to control th operation of the air jets in synchronized operation with the sequence of operations of the machine. For ex-' ample,-if cloth is being made with plain fabric between tuck work such as is used in underwear to obtain shaping or fashioning, or with tight and loose fabric such as is used in foundation gar ments, then it is desirable that the air be turned on at the line where the fabric is to be out. On the other hand, if straight fabric'is being made I have found it desirable to control the solenoid on a time basis independently of the operation of the machine. For this purpose I have provided a clock motor 2| which may be connected to the electric current supply 23 by separate wires through the master switch I9. I have found it desirable to turn the air on every two minutes and to keep it on for a suflicient time to allow the machine to make two or threerevolutions. In this case the clock motor would have a twominute cycle, i. e., thirty revolutions per hour. Other cycles may be used. A clock motor switch 22 may be placed in series betweenthe; electric current supply 23 and the solenoid When controlling the operation of the air jets in time with the-machine itself, I use a special lug 24 on the-main pattern chain to swing. a pivoted lever 25 over a roller 26, thereby depressing the roller (Fig. 3). Depression of th roller operatesa special electric switch 21. This is adapted to be connected in series between the current supply 23 and the solenoid H. The cir-' cuit including the clock motor 2 I- and clock switch 22, orthe circuit including the chain lug 24 and switchZ'l, may be connected alternately intothe current supply solenoid circuit by a twopoint switch 28 (Fig. 4) or by simply changing the wires under the binding post 29.

It will be seen that while my cleaner occupies only the minimum space around the bedplate and knitting-elements, it is well adapted to cleaning all around the machine and with means suited to the conditions atevery point. i'

'machine.- tent will now be set forth. As can be seen in: Figs. 2 and 4 of the drawings, the Jets [3, I4

' can be controlled either from the operations of I claim:

1. A circular knitting machine having a stationary needle cylinder, independent needles therein and one or more brushes revolving about the needle cylinder in close proximity to the needles tocollect the lint in. combination with a stationary compressed air jet adapted to blow lint oif the brushes when they pass the jet, and

"means to operate the air jet intermittently.

2. A circular knitting machine according to claim 1 in which the jet is directed tangentially to the needle circle so as to blow the lint off the 3. A circular knitting machine having a stationary needle cylinder and a fixed brush revolving about the needle cylinder in contact with the needles whereby the brush tends to roll up the lint in balls, in combination with a compressed air supply and a stationary jet connected thereto adapted to blow the balls of lint away-from the fixed brush when the brush passes the jet, and means. adapted to operate the air jet intermittently.

4. A circular knitting machine according to claim 1, in combination with broken yarn de tectors located above the needles and a second jet connected with the air supply some distances below the detectors adapted to blow airupwardly against the detectors to lift off the latter any lint resting on them.

5. In a circular knitting machine according to claim 1, the provision of an air valve to control the air jet and an electric solenoid adapted when i energized to open the air valve, in combination with a starting lever for the machine and an electric circuit for the solenoid adapted to be controlled by the movements of the starting lever.-

6. A circular knitting machine .according to claim 5, in combination with a pattern chain, a

lug on the pattern chain and an electric switch adapted to be closed by said lug, said switch be-. ing in the circuit with the solenoid and the starting lever, whereby the pattern chain lug controls theintermittent operation of the air valve.

7. A circular knitting machine according to. claim 1, in which there is an air valve to control the air jet, an electric solenoid adapted when energized to open the air valve, and an electric v circuit for the solenoid, in combination with a clockmotor and an electric switch in the circuit with the solenoid controlled by the clock motor, whereby the clock motor controls the op eration of the air jet. l

8. A circular knitting machine according to claim 1, in which there is an air valve to control the air jet. an electric solenoid adapted when energized to open the air valve, a starting lever for the machine and an electric circuit for the solenoid adapted to be controlled by the move; ments of the starting lever, the connections between the starting lever anclthe electric switch inthe solenoid circuit being such that when the. starting lever moves to inoperative position "the air jet will be shut ofi'. 9. A circular knitting machine according ,to claim 8, in which there is a two-point master control switch in the solenoid circuit, a clock motor, an electric switch controlled by the motor connectedto one point of the master switch, in

combination'with a pattern chain, a pattern lug thereon and an electric switch controlled thereby connected to the other point of'the master switchQ whereby the intermittent operation of the air jet the machi'neor independently thereof.-

REFERENCES CITED The following references are of record in the file of this patent:

5 UNITED STATES PATENTS Number Name Date 1,889,838 Norman Dec. 6, 1932 2,325,023 Allread July 27, 1943 2,357,714 Vossen Sept. 5, 1944 10 2,422,514 Allen June 17, 1947 2,436,241 Wytovich Feb. 17, 1948 

